[vllm] fix: LoRAModel import path change for vLLM 0.13.0

[HollowMan6]

What does this PR do?

Related to vllm-project/vllm#30253 (comment)

LoRAModel import path was changed from vllm.lora.models to vllm.lora.lora_model.

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[gemini-code-assist]

Code Review

This pull request addresses an ImportError for LoRAModel due to a path change in a recent vllm version by removing the import and the corresponding type hint. While this resolves the immediate issue, I've suggested an alternative approach that preserves the benefits of static type checking. My recommendations involve using a conditional import with typing.TYPE_CHECKING to handle different vllm versions gracefully. This allows restoring the LoRAModel type hint, which improves code clarity and maintainability without causing runtime errors.

[gemini-code-assist]

Code Review

This pull request updates the import path for LoRAModel to support a newer version of vLLM. The changes correctly use a try-except block for backward compatibility. However, the current implementation places the import within a TYPE_CHECKING block, making LoRAModel unavailable at runtime. This is a brittle approach that could lead to future runtime errors. I have provided suggestions to refactor this into a more robust, module-level import, which is a standard pattern for handling such compatibility issues.